This involves a very little economics history. I'll try and keep it brief and simple.
In 1929 the US, and in its wake the world, suffered the great depression. Businesses failed, and as they failed, their employees, having less money, bought less of other people's products, so they failed too. It was massively circular, and the worlds economies came crashing down.
Governments were at a loss of how to deal with it, but in 1935 John Maynard Keynes came out with the economic theory that if government Increased spending, by funding infrastructure investment, it could give people jobs, and money, which they could spend on other people's products. By employing people to build bridges, and other infrastructure, Keynes argued governments would reverse the cycle and the economy would recover.
It worked. It was a massive success. Basically by simply printing money, to pay people to build bridges and such things, the worlds economies were put back on track.
However, around the 1980's based largely on the economics of Milton Friedman the world started to experiment with neoliberalism. Friedman was a big influence on Ronald Reagun and Margaret Thatcher.
For those who don't understand neoliberalism, it's essentially the idea that society is better run by corporations and business, than by government. Hence, lots of privatisation, and banks being deregulated, because business knows best, and free markets are good for everyone.... except it kept screwing up, and we've had boom and bust since, but the richest didn't care, because when it boomed they made money, and when it bust the richest would buy all the stuff (land and factories) the not quite as rich were forced to sell off to stay afloat.
Neoliberalism is essentially Tory Party dogma. So when Labour MP's started buying into it, they were accused of being "Tories". But it wasn't just Labour who bought into it. All of our mainstream parties bought into it. The Tories, Labour and the Lib Dems have all bought into neoliberal dogma.... and it simply doesn't work. It's fine for the good times, but essentially the bubble always bursts.
In 2008 they blamed the banking crash on Leyman Brothers, but it was just another case of the neoliberal bubble bursting, and that particular bank took the hit first, and the rest soon followed.
Now, there are some MP's who get this, and some who don't, or simply choose not to. In the 2010 election, there were a tiny number of MP's in the Labour party who understood it, but it was actually the Green Party and SNP who led the fight against the false austerity the tories were pushing. At a time when we needed to be literally building bridges (or other infrastructure), and invoking Keynesian economics, all of our mainstream MP's were pushing neoliberal Friedman style economics and Austerity on us. Austerity following the 2008 banking crash, was the exact opposite of what we needed.
The fight back started in the Labour Party, where it has now largely been won [edit, and lost again as of 2019] (.... but the Lib Dems and Tories are still playing with neoliberal economics which simply do not work. They have led to the most massive increases in inequality since the 80's, when all the time prior to that, from WWII to the 70's inequality had been decreasing.
Some people talk about Labour being divided, but the fact is, Labour has been having a fight the Lib Dems and Tories have yet to have. The tories won't have it - they're a party for the rich, and they don't care about anyone else. The Lib Dems.... well, they used to be decent party... but they've very much lost their way. They took on Tory Party neoliberal economics... and their current political campaigning seems to be mostly taken from the Brexit Party playbook; Promises smears, lies and no substance. I used to like the Lib Dems but not at the moment. They've a long way to come back.
When people accuse the Labour right, and Lib Dems of being "Tories", what they mean is that they are accusing them of signing up to utterly disreputable neoliberal economics, which favour the rich, create inequality, and screw everyone else.
Keynes' economics worked. It basically rescued the world from the great depression of 1929. Economists know this. I find it hard to believe that our politicians don't have economic advisers, so they also know this. If the Lib Dems have any integrity, at some point in the future they are going to have to have the fight the Labour Party have just had.
That or they are going to have to accept that they're a bunch of Tories.